To dismiss a paper on perpetual motion machines you just need to know the implications of the first or second law of thermodynamics, about which there is, for all intents and purposes, unanimous consensus.
To dismiss attempted translations of the Voynich manuscript, you'd need to read the attempted translation because there is no consensus whatsoever about the manufascript, except for the fact that it is untranslated.
That would only be true if every attempted translation were unique.
In other words, once you've dismissed one paper barking up the wrong tree you can confidently dismiss all the others that appear to be barking up the same tree.
To dismiss attempted translations of the Voynich manuscript, you'd need to read the attempted translation because there is no consensus whatsoever about the manufascript, except for the fact that it is untranslated.